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  #21  
Old 03-19-2009, 06:49 AM
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Originally Posted by Front Range 4x4 View Post
Thanks for the reminder Nathaniel. I should remember to search first.
No worries! There is so much info about your question, I figured I would point you in that direction first, then we could help with specifics.

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Originally Posted by rover67 View Post
welp, tonight I finally got a hold of somebody on 146.460. there were a few guys chatting it up and during a break i threw out my call sign.

anywho, only a short exchange of callsigns and general hellos and goodbyes and I was off, but it was nice to have a good solid contact!

Anyways, thanks again for all the help folks.. this will hopefully become second nature soon!
Glad to hear it!!

I think there are a couple of folks from Longmont and the north suburbs using 146.460 more often. It used to be that we were the only ones on that freq, but I think we encouraged more to use it, which is good. The more we use the airwaves, the more we can justify our ability to have the privilege to use them.
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  #22  
Old 03-19-2009, 08:55 PM
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Originally Posted by rover67 View Post
Hello there folks, anybody want to help school me on the world of HAM tonight? I have my radio installed in the truck and have been listening a bit but am nervous to talk. <snip>
Hey Marco, I heard you this afternoon. I was in the King Soopers parking lot (SoBoRd and 42/95th) on the phone. By the time I was able to throw out my call you must have been QRT or QSYd. But you were 5x9, rock solid. Were you in Lafayette or further out?

EDIT: I should have clarified that I heard you on 146.46 so you were coming in to my radio 5x9 on simplex. So your install seems to be solid and your antenna must be matched pretty well.
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Last edited by jacdaw; 03-20-2009 at 04:24 PM. Reason: clarification
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  #23  
Old 03-20-2009, 08:27 AM
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I have been announching that I am mobile on the 146.46 frequency when I leave work lately in the evenings (usually between 1700 and 1800). Work is on Mcaslin and 36 or thereabouts.

I'll usually stick around on the frequency for a while but sometimes I listen for a few minutes then move to one of the repeaters to hear more conversation and learn. I can only monitor one frequency at a time.

Perhaps I should anounce I am clear and QSY'ing to the new frequency?

Good to hear I was 59, I've been transmitting on lower power (25 watts I think is the radio's medium setting) because I figured out that if If I transmit at 75watts I may reach somebody that I can't actually hear well at all. I was wondering how well it sounded from a known range. When I had my last QSO I got a response to my call at 25watts (he said I was scratchy), and jumped it to 75 watts to finish the conversation. Worked out well.
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  #24  
Old 03-20-2009, 08:36 AM
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I'll be interested to know if you have any luck hearing or broadcasting from Boulder County to folks south of Westminster on simplex. On RS meeting days I've had spotty reception at best, but once I'm south of 120th or so (that infamous Jeffco ridge) things get much better.

I was on last night around 5:30, and checked 146.460, and the Lee Hill repeater. No activity on simplex, and I picked up some random chatter on the repeater.
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  #25  
Old 03-20-2009, 04:21 PM
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Perhaps I should announce I am clear and QSY'ing to the new frequency?
In my 15 years of commuting with ham in the car in northern California, I never heard anyone announce a "clear and QSY" unless contact had been established with another operator. I know there are regionally accepted practices (SoCal is horrible to me) and I have only been in Boulder for three years so I'm still learning the way Front Range operators do things.

I have been in some places where any non-essential traffic is frowned upon and even scolded on air. I've not heard that here at all. The way I understand the operating rules is that we do not use the radio for broadcasting, but specific point-to-point communication. But this allows for CQing on simplex and announcing our presence on a repeater pair to establish a QSO. The rules also allow for a net control station to QST the start of a net so all operators monitoring the frequency will know that a net is about to start.

Nothing says you have to "clear and QSY" but if you're leaving a QSO with multiple operators, it is certainly the courteous way to exit. I've been in round robin commute QSOs where we've had 10 operators, and some of them drop out or get to work or whatever before their next turn. Sometimes they shut down and dissapear. Sometimes they'll break in with their suffix (I'll do it by saying charlie oscar really fast) so they can QRT.
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  #26  
Old 03-20-2009, 05:02 PM
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Originally Posted by Jacket View Post
I'll be interested to know if you have any luck hearing or broadcasting from Boulder County to folks south of Westminster on simplex.
Not to nitpick, but here ya go anyway. You as a responsible ham are not broadcasting, but transmitting. Only KOA and obnoxious CB'ers broadcast, which is making an RF transmission to a wide-ranging audience with no expectation of a direct response. Broadcasters use as much power as they can to reach the maximum number of listeners, while hams use the least amount of power necessary to support their contact. So you might technically broadcast your CQ, you most certainly will reduce power during contact. Right? I know you do go down from 50W to 25W to 10W to 5W during your contact. :-)
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  #27  
Old 03-20-2009, 07:15 PM
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I can say it's pretty cool, Just got back from a ride at Marshall Mesa and right after hopping in the truck I announced I was mobile. Wouldn't ya know Dave shouted back. What I thought was really cool was that during our quick conversation (filled withs uhhs, umms, I guesses, and silly q's "what does S3 mean?" on my part) dave and I lowered our power and the contact remained pretty darn clear.

The initial contact was at 25w (for me) and I lowered to 10w and dave said I was still readable but more scratchy. After that I upped it to 75w thinking dave would say " holy smokes it's like you are right next to me" and to my surprise he responded that I was back to the clarity I was at with 25w. So back to 25w I went.

Cool especially since I was in a hole at the Marshall Mesa trail head near Marshall and Dave was in south Denver.

Still learning here so hopefully the conversation went ok
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  #28  
Old 03-20-2009, 08:30 PM
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Still learning here so hopefully the conversation went ok
No man, it was a great contact. Clear, to the point, etc.

BTW, since you asked about RST and I'm not sure I gave you a clear definition, I will expand on it a little. RST means 'R'eadability, 'S'trength, 'T'one.

So when people say 'You're 5 over 9', 'Got you 59' or something similar, what they are giving you are two things.

The first number is a subjective readability and the second signal strength. The third is tone, which is not used with phone modes (i.e. voice).

So the first is 1 to 5, 5 being clear as sitting next to you and 1 being barely able to understand (obviously anything under 1 would be unintelligible). So I had Marco at R 3 to 4 most of the time, which means I didn't have trouble making out anything you said but there was noise, interference, etc. This could indicate you need more power, different antenna, a better mic, to roll up the windows, etc. In our case it was mostly just interference over the RF link, so power increase, higher gain antenna, etc.

Since most of us are using 2m mobile and handies, the strength is easy to estimate from the meter on the radio. Most of them have 9 bars, dots, numbers or something. You simply use that as a guide to determine received signal strength. Our contact was bouncing on my radio from 3 to 6 bars most of the time and so I said I was getting you about S5 or so.

If you are working HF, CW or AM the signal strength is more important and so they are very interested in the actual strength. On FM that's not quite as meaningful, so we just stick to the straight S-scale and say S9 or higher is just full quieting. What that means is that the modulated carrier is sufficiently strong that your radio has no issue demodulating your voice from the signal, so you get no static or anything, i.e. a fully quiet channel with just information coming out of the speaker.

So for the bulk of us, a contact read back would be a gut readability and simply reading the S-meter on your radio. Oh, BTW, this is really only a simplex thing, giving the signal of a repeater is completely meaningless. You can offer clarity readings (i.e. scratchy or inability to hold the input link) on a repeater contact, but since the repeater is re-transmitting a signal with like 200W from an ideal location, of course you will get S9...

More geeky stuff follows

So if you have a better S-meter you might say 'I'm getting you R,S of 4, 65dB', which means literally that the signal strength at your rig is -65dBm. This is 65dB below standard 0 dBm, which is about 1mW of received power. You might also say you have a contact at '5, 20dB over S9', which means you have a very clear readability and 20dB of additional strength over S9.

To give you a reference, 1mW is about the field strength generated by a wireless mouse or Bluetooth ear piece at 1 meter of distance. So -65dB is 1/1,000,000th (yes, one millionth) of that power. The decibel is 10*log(p1/p2), or for -60dB that's (1000 * 1000) times less power than the 0dB reference. Each 3dB jump is a reduction or increase in power by 2x...

But luckily the S scale is already by agreement within the ITU inherently logarithmic and technical already in dB!

For UHF and VHF S9 = -93dBm and each step down is a -6dB jump, so S8 = -99dBm, S7 = -105dBm, etc. For HF S9 is defined as -73dBm. So a VHF S4 would be roughly -123dBm, which is around 0.01pW, that's 1 x 10^-14 watts (picowatts are 10^-12) at your receiver. If you want a comparison, this is considered within the thermal noise (i.e. background noise) for a satellite downlink channel. But yet you still have another dozen or so decibels of S-scale to go...

So that report of 20dB over S9 means on VHF that you are getting a signal strength of -73dBm (-93dB + 20dB over S9 = -73dB). This is a pretty decent signal for ham radio. But if you want a real comparison, -70dBm is roughly the signal strength of WiFi at its fringe and that's considered a super good ham signal!

So at 30 miles or whatever Marco and I had our 25W contact our radios were picking up signals similar in strength to what your laptop might see at 200 feet and we were perfectly clear in our conversation until we went down to 5W of power (which gave us S1~S2 levels, -125dB!). Pretty friggin' amazing radios if this EE says so himself.
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  #29  
Old 03-20-2009, 08:49 PM
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I should note that you don't have to have a S9 to have R5, it's perfectly possible that a contact is R5 with S6 and vice versa a contact can be S9 with a R3. For example if the mic cable is broken and making intermittent contact but you get full quieting on the link you would be correct is reporting a 'RS of 3 over 9' or you could just as easily report that you have an 'RS of 5 over 5' when you have good readability but a weak signal. This is ideal really because of using the lowest power to hold a good contact and all.
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  #30  
Old 03-20-2009, 09:57 PM
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Yup. And using a repeater colors this as well. You can be getting a strong signal from the repeater from an operator who is barely breaking the squelch of the repeater and thus R1 or worse with an S9 (because the Rx comes from the other operator's input to the repeater, and the Sx comes from your input from the repeater). Or you can be the one on the fringe of the repeater's range, hearing a solid operator into the repeater but you hear R1/S1.

It's much easier to determine the reason for a specific signal report
operating simplex.

Quote:
Originally Posted by DaveInDenver View Post
I should note that you don't have to have a S9 to have R5, it's perfectly possible that a contact is R5 with S6 and vice versa a contact can be S9 with a R3. For example if the mic cable is broken and making intermittent contact but you get full quieting on the link you would be correct is reporting a 'RS of 3 over 9' or you could just as easily report that you have an 'RS of 5 over 5' when you have good readability but a weak signal. This is ideal really because of using the lowest power to hold a good contact and all.
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